The invention relates to implementing a thermodynamic cycle.
Thermal energy from a heat source can be transformed into mechanical and then electrical form using a working fluid that is expanded and regenerated in a closed system operating on a thermodynamic cycle. The working fluid can include components of different boiling temperatures, and the composition of the working fluid can be modified at different places within the system to improve the efficiency of operation. Systems with multicomponent working fluids are described in Alexander I. Kalina's U.S. Pat. Nos. 4,346,561; 4,489,563; 4,548,043; 4,586,340; 4,604,867; 4,732,005; 4,763,480; 4,899,545; 4,982,568; 5,029,444; 5,095,708; 5,440,882; 5,450,821; and 5,572,871, which are hereby incorporated by reference. U.S. Pat. No. 4,899,545 describes a system in which the expansion of the working fluid is conducted in multiple stages, and a portion of the stream between expansion stages is intermixed with a stream that is lean with respect to a lower boiling temperature component and thereafter is introduced into a distillation column that receives a spent, fully expanded stream and is combined with other streams.